1. Technical Field
The present invention relates to a compound capable of improving, in particular, a surface activating property in alkylbenzenesulfonic acids used as surfactants and Brønsted acids, and giving high reactivity as an acid catalyst even with a small amount at a low temperature.
The invention also relates to a manufacturing method of a condensation compound and a manufacturing method of a binder resin that are preferably used in development with a developer an electrostatic latent image formed by an electrophotography or an electrostatic recording method. The invention further relates to a dispersion liquid of condensation compound particles manufactured with the condensation compound and a dispersion liquid of resin particles manufactured with the binder resin, and an electrostatic image developing toner manufactured using these dispersion liquids. The invention still further relates to an electrostatic image developer with the electrostatic image developing toner, and an image-forming method.
2. Related Art
In recent years, with the rapid spread of digitized techniques, improvement of image quality is required in the output of printing and copying by users in general homes, offices and publishing fields. On the other hand, the requirements for lowering and saving energies are increasing for the activities of enterprises and the products resulted from the activities towards the realization of durable society. Accordingly, it becomes necessary to effectuate energy saving also in the fixing processes in the image-forming methods by electrophotography and electrostatic recording that consume great energies, and activities to lower the environmental load in the processes of manufacture of products with the materials. As the countermeasure to the former, a measure of lowering the fixing temperature of toners can be exemplified. By lowering the fixing temperature of toners, it is possible to shorten the waiting time until the fixable temperature of the surface of a fixing member at the input time of electric source, warming up time, in addition to energy saving, and lengthen the lifetime of fixing members.
As the binder resins of toners, vinyl polymers have been widely used so far, but vinyl polymers having a high molecular weight have a high softening point, so that it is necessary to set the temperature of a heat roller high to obtain fixed images having high glossiness, which is contradictory to the conservation of energy.
On the other hand, polyester resins are flexible as compared with vinyl polymers due to their stiff aromatic rings in the chains, and the molecular weight thereof can be set low when the mechanical strength is made equivalent. Further, since polyester resins have an advantage that they are easy in designing as resins for low temperature fixing in points of the entanglement of molecular chains and limiting molecular weight as compared with vinyl-based binder resins, polyesters are widely used as the binder resins for energy saving toners.
Polycondensation of polyester generally necessitates reaction of more than 10 hours under highly reduced pressure with stirring at high temperature exceeding 200° C. by huge power, so that accompanied by the consumption of large quantity of energy. Therefore, vast plant and equipment investments are required in many cases to obtain durability of reaction equipment.